Hearing protector against loud noises

ABSTRACT

The invention relates to a hearing protector for attenuating, selectively or not, noises that can have an intensity of up to 190 dB, designed to be inserted in sealing fashion into the auditory canal. The hearing protector includes a flexible cylindrical body that has a ferrule at each end. At least one of the two ferrules has a channel that runs from one end of the ferrule to the center of the cylindrical body and contains an acoustic filter. When the two ferrules each contain an acoustic filter, the filters may or may not be identical.

BACKGROUND OF THE INVENTION

1. Field of Invention

The invention relates to hearing protectors, and in particular, theinvention relates to a hearing protector to protect against high,continuous or impulsed, noises. The hearing protector can functioneither in a selective attenuation mode or a maximum attenuation mode.

2. Description of Related Art

In the selective attenuation mode, sound attenuation is low for aspecific range of frequencies and increases for sounds with frequenciesabove those in the specified range. Selective attenuation is especiallyeffective for the loudest noises. A sample application of a hearingprotector operating in the selective attenuation mode is theintelligible speech transmission in a noisy environment caused byimpulsed noises, such as gunshots, for example. In this case, thefrequency range in which the attenuation is low is between 100 to 1000Hz. In the maximum attenuation mode, the hearing protector stops allsounds throughout the frequency range, regardless of their intensity.

French Patent Publication No. 2 676 642, filed in the name of theApplicant, discloses a hearing protector that is not cumbersome andcontacts the auditory canal. The protector comprises an elongateflexible body containing selective attenuation means, maximumattenuation means, and a manually controlled plug that makes it possibleto choose the attenuation functional mode to be either selective ormaximum. However, this device requires careful handling by the user whowants to block the auditory canal himself. This manipulation can be doneincorrectly, resulting in inefficient blockage in the selective ormaximum attenuation modes.

SUMMARY OF THE INVENTION

The goal of the present invention is to provide a reliable hearingprotector that does not suffer from the disadvantage of user adjustmentand permits two configurations for noise attenuation that have differentcharacteristics.

Another goal of the present invention is to provide a reliable hearingprotector capable of selectively or automatically attenuating noiseshaving intensities up to 190 dB. The hearing protector is intended to besealingly inserted into the auditory canal of the user. The hearingprotector includes a flexible cylindrical body having a ferrule at eachend, with at least one of the ferrules having a channel that runs fromone end of the ferrule to the center of the body and contains anacoustic filter.

The hearing protector has two ends, both of which can be inserted intothe auditory canal and is referred to as a "double-ended" device. Thiscontrasts with the well-known hearing protector that typically has oneend that can be inserted into the auditory canal, while the other endallows the hearing protector to be gripped so the user can position itin the auditory canal. The present invention has two ends, that may ormay not be identical, either of which can be inserted into the auditorycanal, thus making it possible to choose between two operating modes ofattenuation that may or may not be identical.

The device is useful in the fact that it possesses, in the same hearingprotector, two configurations that can have different attenuationcharacteristics, both obtained by simply reversing the direction of thehearing protector, or ear plug, that is inserted into the auditorycanal.

In a preferred embodiment, the two ferrules are separate parts linked byan internal connector. The internal connector may be a single cylinderpierced by a channel containing an acoustic filter, the cylinder forminga right angle that terminates at a first end of the channel and a secondend at the center of the connector.

The internal connector may also be a single cylinder having a channelthat terminates at three locations, such as at the center of theconnector or at each end of the connector, with the parts of the channelterminating at the ends containing an acoustic filter that may or maynot be identical.

The internal connector may also be composed of three cylindrical parts.The central part may have a channel at its center with a diameterslightly greater than that of the other two parts. The other two partshave a diameter that is essentially equal to or slightly larger thanthat of the channel. At least one of the two parts is pierced by achannel at its center which contains an acoustic filter and communicateswith the channel in the central part. When the two parts each contain anacoustic filter, the filters may or may not be identical.

In an alternate embodiment, the internal connector may have serrations,or ridges, to hold the ferrules in place while in the auditory canal.

In yet another embodiment, the hearing protector may have tapered ends.

Preferably, each ferrule of the hearing protector is provided with anessentially hemispherical face of which the narrower side is intended tobe inserted first into the auditory canal.

Advantageously, the body of the hearing protector may be provided withflexible annular fins having a diameter that increases from the insideto the outside of the auditory canal in order to wedgingly secure it inthe auditory canal.

The hearing protector makes it possible to perform nonlinear soundfiltration by choosing the correct acoustic filter.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in conjunction with the followingdrawings in which like reference numerals designate like elements andwherein:

FIG. 1 is a longitudinal view, in partial section, of a "double-ended"hearing protector according to a preferred embodiment of the presentinvention;

FIG. 2 is a longitudinal section view of a "double-ended" hearingprotector according to a second embodiment of the present invention;

FIG. 3 is a longitudinal section view of a "double-ended" hearingprotector according to a third embodiment of the present invention;

FIG. 4a-4c are longitudinal views, in partial section, of differentconfigurations of the internal connector that join the two ends of thehearing protector according to the present invention;

FIG. 5 is a perspective view of an internal connector for the two endsof the hearing protector according to an embodiment of the presentinvention;

FIG. 6 is a longitudinal view, in partial section, of a hearingprotector according to a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is a longitudinal view, in partial section, of the hearingprotector according to one preferred embodiment of the presentinvention. The hearing protector includes a body 1 that is molded to fitin the auditory canal of the user. The body 1 is pierced by a channel 2that runs from an end of the body 1 and terminates in the center of thebody 1. The channel 2 contains an acoustic filter 3 that allows forexample the selective and nonlinear filtration of sound. The other endof the body 1 is not perforated and allows maximum attenuation,regardless of the frequency and amplitude of the sound. Ideally, thebody 1 has a length between 2 cm and 4 cm and is composed of a flexiblematerial.

FIG. 2 is a longitudinal section view of the hearing protector accordingto a second embodiment of the present invention. The hearing protectorincludes a body 1 pierced by a channel 2 that terminates at each end ofthe body 1, as well as the center of body 1. The channel 2 also containsan acoustic filter 3 at each end. The filters may or may not beidentical.

Referring to a third embodiment illustrated in FIG. 3, the hearingprotector includes two cylindrical hollow ferrules 4 and 7 and aninternal connector 8. The ferrules 4 and 7 are separate pieces that fitinto one another and are joined by the internal connector 8 to keep theferrules 4 and 7 together. Each ferrule 4 and 7 is provided with asubstantially hemispherical face 6. The narrower portion of the face 6is designed to be inserted first into the auditory canal. Thesubstantially hemispherical face 6 ensures tightness between the hearingprotector and the auditory canal. As illustrated in FIG. 3, at least oneof the two ferrules, in this case, ferrule 4, is pierced by a channel 5at its center. One of the two ends of the internal connector 8 thatcontains an acoustic filter 3 is inserted into at least one of the twoferrules 4 and 7. The acoustic filter 3 permits the selective non-linearfiltration of sounds. The second ferrule, in this case, ferrule 7, neednot be perforated and will allow maximum attenuation regardless of thefrequency and amplitude of the sound. The internal connector 8 ispierced by a second channel 9 that connects at a first end with thefirst channel 5, which contains an acoustic filter 3, allowing for theuse of the acoustic filter 3, and at a second end with the center of theconnector 8. The second channel 9 is formed at a right angle to thechannel 5.

Alternatively, in another embodiment, the internal connector 8 may alsohave a channel that extends in three locations, the center of theinternal connector 8, as well as at each end of the internal connector8. The portion of the channel that terminates at each end contains anacoustic filter 3 that may or may not be identical.

As shown in FIG. 4a, the internal connector 8 may include a singlecylinder consisting of three cylindrical parts 10, 11, and 12. Thecentral part 12 is pierced by a channel 9 at its center and has adiameter that is slightly larger than that of the other two parts 10 and11. The two parts 10 and 11 have a diameter that is essentially equalto, but slightly larger than that of channel 5 in order to hold theassembly together. At least one of the two parts 10 and 11 is formedwith channel 5, which contains an acoustic filter 3 and communicateswith channel 9 in the central part 12, as shown in FIG. 5.

The internal connector 8 may have serrations, or ridges, as shown inFIGS. 4b and 6, or the internal connector 8 may have tapered ends 13 and14, as shown in FIGS. 4c and 5. In the case when the internal connector8 is in three parts, the two parts 10 and 11 will have the serrations,ridges, or tapered ends 13 and 14.

One of the two ferrules has a perforation that, when joined to connector8, is aligned with that of the central end of channel 9 located in part12.

FIG. 6 is a longitudinal view, in partial section, of the hearingprotector according to a fourth embodiment of the present invention. Thehearing protector is provided with flexible annular fins 15 on theferrules 4 and 7 to wedge the hearing protector against the walls of theauditory canal. The fins 15 may have a diameter that increases from theinside to the outside of the auditory canal.

The hearing protector, according to the present invention, is especiallyuseful for individuals who are exposed to very loud engine and weaponnoises, such as the crews of airplanes or military vehicles onexercises, for example. The hearing protector, according to the presentinvention, can also be used effectively by other personnel exposed tohigh-intensity noises in their working environments, such asconstruction sites and quarries for example.

While this invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, the preferred embodiments of the invention as set forthherein are intended to be illustrative, not limiting. Various changesmay be made without departing from the spirit and scope of the inventionas defined in the following claims.

What is claimed is:
 1. A hearing protector capable of selectively orautomatically attenuating noises having intensities up to 190 dB, thehearing protector being intended to be sealingly inserted into anauditory canal of a user, the hearing protector comprising:a cylindricalbody having a center, a first end and a second end; a channel extendingfrom at least one of said first and said second ends of said body tosaid center of said body; said channel contains an acoustic filter; anda ferrule at each of said first and said second ends, wherein saidferrules are separate and said cylindrical body forms an internalconnector linking said ferrules.
 2. The hearing protector according toclaim 1, wherein said internal connector is a single cylinder, saidchannel forming a right angle and having a first end of said channelcontaining said acoustic filter and terminating at at least one of saidferrules and a second end of said channel terminating in said center ofsaid internal connector.
 3. The hearing protector according to claim 1,wherein said channel in said internal connector terminates at saidcenter of said internal connector and at said first end and said secondend of said internal connector, said first end containing said acousticfilter and said second end containing a second acoustic filter.
 4. Thehearing protector according to claim 3, wherein said acoustic filter isidentical to said second acoustic filter.
 5. The hearing protectoraccording to claim 3, wherein said acoustic filter is not identical tosaid second acoustic filter.
 6. The hearing protector according to claim1, wherein said internal connector includes a central cylindrical parthaving a central diameter, a first cylindrical part having a firstdiameter and containing said acoustic filter and a second cylindricalpart having a second diameter, said central diameter being larger thansaid first diameter and said second diameter, said first diameter andsaid second diameter being larger than said channel.
 7. The hearingprotector according to claim 6, wherein said second cylindrical partcontains said second acoustic filter.
 8. The hearing protector accordingto claim 7, wherein said acoustic filter and said second acoustic filterare identical.
 9. The hearing protector according to claim 7, whereinsaid acoustic filter and said second acoustic filter are not identical.10. The hearing protector according to claim 1, wherein said internalconnector has serrations for securing said ferrules to said internalconnector.
 11. The hearing protector according to claim 1, wherein saidinternal connector has ridges for securing said ferrules to saidinternal connector.
 12. The hearing protector according to claim 1,wherein said internal connector has tapered ends.
 13. The hearingprotector according to claim 1, wherein said ferrules each have anessentially hemispherical face having a narrow side, said narrow sidesbeing designed to be inserted into the auditory canal of the user first.14. The hearing protector of claim 1, wherein said cylindrical body isprovided with annular fins, said fins having a diameter that increasesfrom said first and second ends of said cylindrical body toward saidcenter of said cylindrical body, the hearing protector being wedginglysecurable within the auditory canal of the user.
 15. The hearingprotector according to claim 1, wherein said acoustic filter permitsnon-linear filtration of sound.